1. Field of the Invention
The present invention relates to an exposure apparatus equipped with a substrate supervisory apparatus in which a plurality of various reticles or masks to be used in a semiconductor manufacturing apparatus, a liquid crystal substrate manufacturing apparatus or the like can be stored and supervised constantly under a clean condition and a desired reticle or mask can be taken out for use as required.
2. Related Background Art
In a photolithography process constituting a semiconductor manufacturing process or a liquid crystal display device manufacturing process, a circuit pattern is printed on a wafer by use with a reticle or a mask. Usually, patterns to be utilized in respective photolithography processes are different from each other. Therefore, a large number of different reticles or masks are needed for respective photolithography processes. And, a desired reticle or mask is selected from a large number of different reticles or masks to effect a photolithography process. Usually, a large number of reticles or masks are stored or supervised in a reticle stocker or a reticle changer constantly. When storing a reticle or mask in such a supervisory apparatus, it is necessary to manually input the information of the reticle or mask in a control computer. For that reason, the identification information is written on the reticle or mask. And, an operator observes the identification information of the reticle or mask visually to check it by opening its substrate case and thereafter inputs the information from a console. In another case, the identification information of a reticle or mask is written on a substrate case. Then, the operator inputs the identification information from the console by visually observing the identification information on the substrate case. Recently, the identification information of a reticle or mask on a substrate case is indicated by a bar code, making it possible to input the identification information halfway automatically. Similarly, when taking out the reticle or mask from the supervisory apparatus together with the substrate case, the above-mentioned operation is carried out.
However, in the above methods, as the operator checks visually the identification information or identification mark on the substrate such as the reticle or mask and inputs it manually, there is a problem that the operator often reads and inputs the identification information of the substrate or the substrate case erroneously. Similarly, when the operator reads the identification mark such as the bar code on the substrate by use with a bar code reader, the operator's manual or visual operations are interposed invariably, so that there is a danger of inputting wrong information. Further, there is a method that identification marks given to a substrate such as a reticle or mask and a case for containing the substrate are automatically read by the apparatus and the read information is processed as an apparatus constant (parameter). However, in this case, when the reticle or mask contained in the substrate case is not properly combined with the substrate case, the comparison thereof cannot be conducted, so that a wafer is exposed by a stepper, an aligner or the like with the wrong reticle or mask. Therefor, if the identification mark of the reticle or mask and that of the case are automatically read and compared with each other, such a problem can be solved. However, therefore, it is necessary to provide an exposure apparatus or the like with a built-in device for automatically reading the information pattern such as the identification mark on the substrate case. In this case, as the automatic reading device is provided in the vicinity of a substrate case loading section, the operator would be injured if the automatic reading device happens to be activated while the operator is loading or replacing the substrate case.